What's the Safe Word?

Progressing ever onward:

BAGHDAD, May 3 (Reuters) - Four U.S. government contractors, all from the Philippines, were killed in a rocket strike on the heavily fortified Green Zone compound in Baghdad on Wednesday, the U.S. embassy said on Thursday.

It was one of the deadliest rocket attacks on the Green Zone in the Iraqi capital since the U.S.-led invasion in 2003.